We all received fraud orders. I'm wondering what fraud checking methods are you using.
Are you checking IPs before opening an account? If yes, what tool are you using?

48 hours

Use AVS (address verification system)
Use CVV2 (that funky 3 or 4 digit code)
Verify IP address origin and domain name registration if transfering.

Also, our billing software, modernbill, sends emails on declined orders. Many times it may take someone a few tries to get a card/address that is accepted. When we get a whole string of declines we perk our ears up and get ready to REALLY go through with a fine tooth comb before we let the next one through.